Security firm Bit9 says a majority of smartphones are running out-of-date and insecure operating systems that present a threat to critical business data. It has created a list of 12 of the most vulnerable smartphones. Guess who dominates the list?

The top five phone makers held their ground in 2011's first quarter, but gains by smaller manufacturers undercut some of their market share, according to IDC. Apple was a bright spot, says the research firm.